MOUNTING STRUCTURE OF GLASS SUPPORTING PLATE

摘要

PURPOSE:To enable mounting of the glass of an original plate without the need for adjustment, by providing 3 pieces of posts having exact positional accuracy to the housing of an exposure optical system and assembling a glass supporting plate thereto in a 3-point supporting state. CONSTITUTION:Both side walls of the housing B of an exposure optical system are provided with 3 pieces a set of posts 55A-55C in the respective two end parts and intermediate part thereof in the positions deviated from each other in the transverse direction of the housing B so as not to be arrayed on one straight line. The top surfaces thereof, that is, mounting surfaces 56 are made flush. A glass support plate 57B is fixed by means of mounting screw 58 on the respective sets of the right and left posts. If the glass of the original plate are fixed between the right and left glass support plates so as to cover the upper part of the housing B, the adjustment for the parallelism of the original plate glass is not required at all.